Farm Boy

[Dalboy]

Nice progress with the Head 

Good to come back after a setback - isn't it 

Per     

Thank you. Yes this seems to be going right I have drilled the inlet and exhaust posts as well as a locking thread for the rocker arm pillar. Forgot to take photos. Just need to drill out for the spark plug now started to set up for that operation. Hopefully get that done tomorrow which will complete the machining for the head, then onto the bits and pieces that fit to the head.

[Dalboy]

Except for the spark plug thread which is 1/4" X 32 and I only own a 1/4" X 40 which I seem to have a lot of, so have to order these are ME threads. The head machining is now complete, time to start on some of the furniture for the head like making valve springs and rocker assembly. In the last photo(sorry about the quality) you can make out where the inlet and exhaust ports enter the valve guides. The four holes which can be clearly seen in the bottom of the head photo are for head bolts, the other hole seen in the top of the head is for the rocker arm support and the little hole in the side for a grub screw to lock the support in place.
It seems as if everything turned out OK as closer to completion of the head I was worried that if something went wrong there is a lot of work to get back to here.

[Jasonb]

Following along

One point to watch is that glow and miniature spark plugs are threaded 1/4 x 32 UNEF not ME - different angle

[Dalboy]

Following along

One point to watch is that glow and miniature spark plugs are threaded 1/4 x 32 UNEF not ME - different angle

Thank you Jason I have ordered a UNEF tap should be here by the 5th. Learning as I go from many people as well as a few mistakes but enjoying the journey.

[Dalboy]

Very little done today just the valve spring keepers, made from stainless steel the measure 0.400" X 0.125" with a 0.125" hole for the valve stem, and also sized a small piece of brass for the rocker arm ready to be drilled and machined.

[Dalboy]

Finally got around to the rocker arm and a small steel bearing which will push on the exhaust valve. As can be seen it is just a fraction over 1 1/2" long.

Next job the rocker arm support.

[Don1966]

 ……….


 
Don

[Dalboy]

Been a bit slow on this build.

I did manage to make two pins for the rocker arm, sorry no photos.

Then I made a start on the conrod I use the term loosely as it took three failed attempts before managing to get to this stage (all down to me making silly mistakes). Some marking out and made some filing buttons for the small end. At least now it is starting to look the part with a couple more machining operations to do, one being to machine down both sides to lighten it. This is where I need to make a plate to hold the parts which I so happen to have started a while back but need to drill and tap some holes as well as make some clamps.

The second job is to shorten the big end clamp as I left it over long to aid in turning the outer edge of the big end.

[Roger B]

Coming along nicely   

Although as Jason says the plug thread is a UNEF an ME thread works fine for model engine use.

[Dalboy]

Coming along nicely   

Although as Jason says the plug thread is a UNEF an ME thread works fine for model engine use.

Thank you Roger, slowly getting there. I have drilled the holes in the plate now and started to tap the holes, then it is onto some clamps. It will be nice to complete the plate as I am sure it will be useful in the future for other jobs.

I have now got the correct UNEF tap.

[Dalboy]

I should really complete the con rod but as I was away the weekend I thought something small before resuming on that. So I found the oilers for the crank shaft bearings and started on the first of the two, made from brass. I still need to drill out the larger hole in the top but that will wait until I have got the second one to this stage before I drill and tap a piece of metal on the lathe to screw these into to do that operation.


They do not show any caps for these but I may make a couple of them later on.

I did have a go at grinding my first form tool for the outside shape and pleased the way that and the oiler looks.

[Dalboy]

Got around to getting the con rod complete first part was to mount it on the platter that I made and set it up to mill out the recess I had to do this 4 times total because of the taper.



The next up was to slim down the big end cap as it was too large. The screw that you can see in the big end is not a mistake but designed to be like that when I make the big end bearing I have to make a cut out on both sides to allow for them. Also seen is the little end bearing which is a tight fit. Final job was to make the cut out for the little end bearing oil way which can be seen in the second photo along with the oil hole for the big end.

[Admiral_dk]

That is a good looking Rod and should do it's job well 

Per     

[Dalboy]

Thar is a good looking Rod and should do it's jobe well 

Per     

Thank you but it did take a few attempts as I was not happy with some of them

[Admiral_dk]

I'm pretty sure we all has been in that situation at some point .... 

Per